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1.
大鹏湾沙头角海域富营养化与赤潮发生的初步研究   总被引:1,自引:1,他引:0  
报道南海大鹏湾沙头角海域由于工业废水和生活污水的大量流入,使该海域氮、磷和化学需氧量逐年升高,使其富营养化程度值达1.497~11.773,因而近年来冬春季节赤潮发生频繁。主要的赤潮生物有夜光藻NoclilucaSctutllams、裸甲藻Gymnodiniumsp.,中肋骨条藻Skele-tonemaCostatum、海洋原甲藻Prorocentrummicans、海链藻Thalssiosirasp.和角毛藻Chaelocerassp.等。由于该海湾是半封闭性海域,因而赤潮发生的强度较大,其数量为2.7×10 ̄6~8.4×10 ̄4个/m ̄3,生物多样性指数为0.146~0.250.其毒性较大,危害沿岸渔业生产。  相似文献   

2.
西秦岭迭部地区早志留世四射珊瑚动物群   总被引:5,自引:5,他引:0  
西秦岭迭部地区下志留统拉垅组四射珊瑚已报道8属10种,作者近年对该珊瑚动物群详加研究,经鉴定计有9种,13属。18种,描述其中11属12种(包括5新种),即Brachyelasma sp.,Paramplexoides sp., Kodonophyllum cf.leijiatunensis Ge et Yu,Eostauria minor(Chen),Amplexoides chaoi(Grab  相似文献   

3.
内蒙古始新世梳趾鼠类化石   总被引:6,自引:6,他引:0  
王伴月 《古脊椎动物学报》2001,39(2):98-114,T001,T002
描述了4属10种梳趾鼠类化石(Gobiomys neimongolensis, G. exiguus(新种), G. cf.G.exiguus,G.asiaticus(新种),Gobiomys?spp.,Advenimus cf.A.bohlini,A.cf.A.burkei, Yuomys sp.和Protataromys sp.).以Mergenomys neimongolensis作属型种建了一新属,Gobiomys。其特征是:门齿孔大;具P3;颊齿齿冠低,主尖明显,但不膨大,齿凹开阔;P4/p4非臼齿化;上臼齿宽大于长,后脊较发育;M1和M2具内脊;下外脊和下次小尖位置偏外。G.exiguus的特点是:个体较小,上颌骨颧突根在P3之前,下臼齿缺下原失后臂舌部、下内尖臂和下前齿带.G.asiaticus的上颌骨颧突后缘在P3的外方;臼齿具较发达的齿脊;上臼齿较宽短,后小尖较弱;下臼齿具较发达的内尖臂和前齿带。 Gobiomyidae新科包括Gobiomys, Mergenomys,Youngomys和哈萨克斯坦的未命名的新属等4属,组成与梳趾鼠科相对的姐妹群。其主要特征是,下颌骨缺咬肌窝上嵴。颊齿低冠,近于丘形  相似文献   

4.
范亚文  包文姜 《植物研究》1997,17(4):371-376
利用光学显微镜和扫描电镜对东北异极藻科植物3属8个分类单位即:异极藻属2种2变种1变型:细异极藻箭头变处G.sabtile var.saggita(Schum..)Cl.K.,缢缩异极藻头状变种意大利变型G.constrictum var.capitatum f.itallica Mayer.,柔弱异极藻G.tenellum Kutz.,半孔异极藻G.semiapertum Grun.长异极藻延长  相似文献   

5.
本文描述了1981年发现了于四川省的蠓科裸蠓属二新种。分别命名为漫游裸蠓Atrichopogon(A.)planetus(采自泸定县)和四梗裸蠓A.(Ps.)tetramischus(采自南川县)。二新种的模式标本均收藏于北京医学昆虫标本馆。  相似文献   

6.
对1402份来自于东北、华北及西北地区的土样进行裸胞壳属(Emericela)菌的分离。结合菌落形态及扫描电镜下子囊孢子的形态将各菌鉴定到种。结果表明我国北方地区分布有8个种,1个变种,分别是无冠裸胞壳(Emericelaacristata)、皱折裸胞壳(4Emericelacorrugata)、茴香裸胞壳(Emericelafoeniculicola)、宫治裸胞壳(Emericelamiyaji)、构巢裸胞壳(Emericelanidulansvar.nidulans)、构巢裸胞壳宽脊变种(Emericelanidulansvar.lata)、四脊裸胞壳(Emericelaquadrilineata)、褶皱裸胞壳(Emericelarugulosa)及波状裸胞壳(Emericelaundulata)。除银川地区以Emericelaacristata为优势菌外,各地区以Emericelanidulans最为常见。文中对常见菌种进行了简要的概述,对在我国较少见的种进行了详细的描述和讨论  相似文献   

7.
三白草科的比较胚胎学研究   总被引:5,自引:1,他引:4  
研究了裸蒴(GymnothecachinensisDecne)胚胎的发育,同时对三白草(Saururuschinensis(Lour).Baill)和蕺菜(HouttuyniacordataThunb.)的胚胎也进行了观察,并对三白草科(Saururaceae)各属间的胚胎学特征进行比较,以探讨三白草科的内的系统关系。裸蒴具腺质绒毡层。小孢子同时型,极少数小孢子弱细胞的减数分裂II不进行,形成有壁  相似文献   

8.
顾海峰  孙军  邹迎麟  方琦  蓝东兆 《生态学报》2006,26(4):1021-1027
在2003年厦门港发生的一次裸甲藻赤潮中分离得到了纤小裸甲藻(Takayama pulchellum),并对其形态学进行了光镜和电镜的观察,该株藻细胞个体较小,长约20~23μm,宽约14~20μm.藻细胞外表卵圆形,细胞上壳有一条明显的S形顶沟,顶沟是特异性的反S形.与模式种相比,这一株裸甲藻细胞核更靠上部,大部分细胞横沟都没有偏移.纤小裸甲藻在盐度为28时比生长率最大,达到0.42,随着盐度下降,比生长率也跟着下降,当盐度下降到16时,生长率为0.盐度范围在8~16时,超过80%的藻类能存活48h;当盐度低于4时,生长率和存活率都为0.24~27℃是纤小裸甲藻的最适生长温度,比生长率超过0.50,当温度升到30℃时,生长率急剧下降到约0.35.毒素测定结果显示该株裸甲藻不含麻痹性贝毒和神经性贝毒.本株纤小裸甲藻大亚基D1~D2区序列长度为721bp,与基因库中该种的一株相似种同源性超过99%.对18株裸甲藻转录间隔区(ITS)序列建立的系统进化树显示,纤小裸甲藻和Karlodinium micrum的距离最近,通过ITS序列建立的系统发育树大致能够把Akashiwo属、Karenia属、Karlodinium属和Takayama属与Gymnodinium属区分开来.  相似文献   

9.
王耀 《古生物学报》1996,35(6):702-713
描述了豆海百合类2属7种,它们是:Pisocrinus(P.)pilula,P.(G.)kosovensis,P.(G.)bohemicus,Pampisocrinusollula,P.Sphericus,以及Pisocrinus(G.)brevissp.nov.和Parapisocrinuspateriformissp.nov.;并首次发现了P.(G.)bohemicus萼杯内腔的内部钙质骨胳构造。同时,还就波希米亚豆海百合种内变异和豆海百合类的对称性进行了研究。  相似文献   

10.
王文清  刘杰 《生命科学》1994,6(3):35-36
脑金属硫蛋白GIF及其功能研究王文清,潘宪明,刘杰(北京大学技术物理系100871)(美国Kansas医学中心)近年来在正常人脑皮层中发现了一种新的金属硫蛋白异构体,称GIF(Gf。Wthlnhibi-toryFactor,1991,Yok。Uchi...  相似文献   

11.
春季赤潮频发期东海微型浮游动物摄食研究   总被引:50,自引:4,他引:46  
2002年4~5月在东海长江口及其邻近水域的8、11、14、23和28号5个典型站位采样。用现场稀释法对春季东海水域浮游植物的生长率和微型浮游动物对浮游植物的摄食压力等方面进行了研究.结果表明,微型浮游动物的摄食行为在东海赤潮过程起到关键作用.各站位微型浮游动物主要以急游虫、红色中缢虫和夜光藻为主,在种类上砂壳纤毛虫是主要的类群.微型浮游动物的摄食速率范围在0.28~1.13d-1,对浮游植物现存量的摄食压力范围在35.14%~811.69%。对浮游植物潜在初级生产力的摄食压力范围在74.04%~203.25%,对浮游植物碳的摄食率范围在9.58~97.91μg·L-1·d-1,靠近岸边的站位,微型浮游动物的摄食速率、对浮游植物现存量的摄食压力和对浮游植物碳的摄食率相对较高。而远离岸边的站位对浮游植物潜在初级生产力的摄食压力却较高.与世界其它海区比较此水域微型浮游动物摄食压力处于较高水平.急游虫是控制东海主要赤潮原因生物具齿原甲藻生长的关键种类.  相似文献   

12.
A red tide composed mainly of two Prorocentrum species was found near Kadan Island, southern Myanmar coast, on March 14, 2012. This is the first record of a red tide in the Myanmar coastal area. The red tide included three different harmful dinoflagellates: Prorocentrum rhathymum, Prorocentrum shikokuense and Alexandrium affine. Strains of these species were successfully cultured and examined with detailed morphological observation and DNA (28S rRNA gene) analyses. The strains were subjected to growth experiments under different temperatures to understand their growth capabilities. The experiments were carried out at four different temperature regimes (15, 20, 25 and 30 °C). A. affine exhibited low tolerance for the low temperature regime (15 °C), despite records of its presence in northern temperate regions, indicating this strain is adapted to the tropical environment in Myanmar. P. rhathymum and P. shikokuense exhibited broad tolerance to all given temperature ranges and showed high division rates, providing the physiological basis to form red tides.  相似文献   

13.
我国东海赤潮原甲藻应属哪种?   总被引:20,自引:3,他引:17  
齐雨藻  王艳 《应用生态学报》2003,14(7):1188-1190
阐述并讨论了中国东海长江口外经常发生的原甲藻赤潮原因种的种类认知问题.论述了自从Stein提出具齿原甲藻(Prorocendrum dentatum Stein)新种后迄今中外专家报告该种的描述及分布,并对比了具齿原甲藻与长江口的原甲藻的异同.研究证实我国东海的原甲藻与具齿原甲藻有较大的差别,主要表现在体积大小、藻体末端形态以及藻体前端突起的大小和形态等方面.本文汇集了国内外对具齿原甲藻与我国原甲藻的研究成果,对比认为。我国长江口外经常发生赤潮的原甲藻为东海原甲藻(Prorocendrum donghaiense Lu).文中还讨论了由陆斗定发表的东海原甲藻需要补充修正的观点.在过去的数年中,我国东海长江口海域频繁爆发大面积的原甲藻赤潮,但对于赤潮原因种原甲藻(Prorocentrum)的定种问题存在两种不同的观点,一种观点认为本种是具齿原甲藻,另一种观点认为是东海原甲藻.为了阐明此种原甲藻的命名问题,于2002年11月在深圳召开了题为“我国东海赤潮原因种原甲藻分类学国际研讨会”.认为是P.dentatum的依据是长期以来国际上通常把类似我国东海的原甲藻定为P.dentatum,其根据是它的前端有突起等.而持不同观点的专家认为我国东海的这种原甲藻在细胞长度上与Stein描述的原P.dentatum差异很大,并且除少数样品末端尖伸外,大多数细胞末端是钝圆的.专家们还认为在日本、韩国等亚洲海域分布的被报告为P.dentatum的原甲藻与我国东海的此种原甲藻为同一种.综观各种观点,作者认为东海本种原甲藻应为东海原甲藻.  相似文献   

14.
Preliminary studies on eutrophication and red tide problems in Bohai Bay   总被引:11,自引:0,他引:11  
A study was carried out in 1978–1981 on the relationship between eutrophication and the occurrence of red tides in Bohai Bay.An assessment method using a single parameter as well as the multiparameter Trophic State Index was adopted. DIN, DIP, COD loadings and concentrations and phytoplankton community (species composition, diversity index, standing crop, chlorophyll a and primary productivity) were used as parameters. The western part of the bay and two sewage outfall sites showed the highest values of chlorophyll a, nitrate, phosphate, standing crop, primary productivity and the greatest population instability. Therefore, Bohai Bay, can be regarded as mesotrophic, but its estuary eutrophic. Anthropogenic factors are mainly responsible for its eutrophication. A relationship between environmental factors and red tide species was found. Noctiluca miliaris, Prorocentrum minimum and Skeletonema costatum have their bloom periods from July to September and are the most significant species.  相似文献   

15.
湛江港湾潜在赤潮生物的时空分布及其影响因素   总被引:1,自引:0,他引:1  
2009年2月(冬)、5月(春)、8月(夏)和11月(秋)分别对湛江港湾的浮游植物和环境因子进行了调查,并对该海域潜在赤潮生物的时空分布及其影响因素进行了分析。结果表明,湛江港湾海域潜在赤潮生物共有126种,其中硅藻门26属85种,占潜在赤潮生物种类数的67.5%,甲藻门14属36种,占潜在赤潮生物种类数的28.6%,蓝藻门1属2种,占潜在赤潮生物种类数的1.6%,金藻门2属2种,占潜在赤潮生物种类数的1.6%,针胞藻纲1属1种,占潜在赤潮生物种类数的0.8%。种类数以春季最多,达89种,秋季次之,为71种,夏季61种,冬季最少,仅有58种。细胞丰度在12.36×104~43.55×104cells·L-1,春季最高,夏季次之,冬季最低,从各主要优势种的细胞丰度和细胞大小判断,该海域潜在赤潮生物的丰度均未达到赤潮发生的阈值。4季均出现的种类共有31种,季节相似性指数在0.43~0.50。优势种共有19种,全为硅藻,没有观测到甲藻。优势度最大的种类主要有浮动弯角藻(Eucampia zoodiacus)、旋链角毛藻(Chaetoceros curvisetus)和中肋骨条藻(Skeletonema costatum),没有全年优势种。中肋骨条藻、旋链角毛藻和冰河拟星杆藻(Asteri-onellopsis glacialis)为3季优势种。分析表明,潜在赤潮生物细胞丰度与叶绿素a、水温、盐度和pH值存在着极显著的正相关,与DIN和SiO32-存在着极显著的负相关,与PO43-不存在显著相关关系。  相似文献   

16.
Dinoflagellates collected during red tide events in Bahia Mazatlan, Mexico during the early spring of 1999 and 2000 appeared under LM to belong to Prorocentrum mexicanum Osorio‐Tafall. Observations with SEM of those populations showed marked differences in shape and microornamentation from the related species, Prorocentrum rhathymum Loeblich III, Sherley and Schmidt. In P. mexicanum, the presence and dimensions of poroids, the uneven distribution of trichocyst pores not located in depressions, and the general architecture of the periflagellar region are more closely related to Prorocentrum caribbaeum Faust. Also, P. mexicanum has a three‐horned (sometimes two‐horned) spine and is deeper in the anterior than the posterior region, whereas P. rhathymum has a simple small spine and its sagittal view is oval. Furthermore, the number and distribution of trichocyst pores in the periflagellar area is different between the two species, being located on both valves in P. mexicanum and only on the right valve in P. rhathymum. To date, true P. mexicanum has been described only from plankton sampling, whereas P. rhathymum was frequently mentioned associated with floating detritus (macroalgae) but also forming red tides. Altogether, the evidence presented demonstrates that P. mexicanum (planktonic) and P. rhathymum (epibenthic) are distinct species and are not synonyms, as is often accepted.  相似文献   

17.
长江口赤潮高发区浮游植物与水动力环境因子的分布特征   总被引:20,自引:1,他引:19  
报道了2002年春季长江口海域(30°50′~31°50′N,121°50′~123°00′E)的22个大面观察站和一个昼夜连续观察站的水样和网样浮游植物的种类组成、丰度分布与水动力环境因子、营养盐的关系.结果表明,长江口区共有浮游植物5门45属110种.主要赤潮生物优势种为中肋骨条藻(Skeletonema castaturn)和具齿原甲藻(Prorocentrum dentatum)等.浮游植物丰度的昼夜变化白天大于夜间,垂直分布不明显.浮游植物主要生态类型可划分为:沿岸河口低盐半咸水类群、沿岸偏低盐广布性类群、外海高盐暖水性类群等.长江口区浮游植物丰度在1.6×10^3~75.2×10^3个.dm-3.浮游植物的种类组成和丰度分布与长江冲淡水密切相关.在该区域存在三股不同性质的水,即长江河口水、长江冲淡水及外海水(台湾暖流)影响着浮游植物的分布.  相似文献   

18.
《农业工程》2022,42(5):501-510
27 points were surveyed, and then algae and seawater samples were collected in Hai-tan Strait. The correlation on HAB (harmful algae blooms) species and environmental factors were studied. Water temperature (T) and salinity (S) ranging from 11.9 °C to 27.8 °C and 20.4 to 33.7 in the year, respectively. Dissolved inorganic nitrogen (DIN) in surface water ranged from 0.098 to 0.776 mg·L?1, PO4-P ranged from 0.0016 to 0.0729 mg·L?1. And Eutrophication index (E) ranged from 0.03 to 13.8, varied different. 102 species of algae belonging to 4 classes and 52 genera were identified. The diversity was increasingly from winter to summer, decreasingly from summer to autumn, highest in summer. 49 species of red tide organisms were found in Hai-tan Strait, main two classes were Bacillariophyta and Pyrrophyta. Ceratium tripos and Noctiluca scintillans were dominant species in spring, Skeletonema costatum was common, and was also mainly HABs dominant species in summer, autumn and winter. Pearson correlation and Canonical correspondence analysis (CCA) showed that environment factors had significant correlation with dominance HABs species in different extent, and the ordination result was that S(Salinity) > T(Temperature) > pH > E(Eutrophication index) > DO(dissolved oxygen) > DIN > PO4-P. Prorocentrum donghaiense, Skeletonema costatum, Noctiluca scintillans and Karenia mikimotoi caused many times red tide in 2011 to 2016. However, Prorocentrum donghaiense and Karenia mikimotoi cell density was low in survey year. North of the strait and east coast of the southern strait were sensitive sea area of red tide. The work highlights for the first time ecological characteristic of HAB was studied in Hai-tan Strait. Further, the data and results of this study will help us to improve efficiency for controlling HAB. Even, it is worthwhile to the management and response to the red tide disaster. Ordination result can also be a good indicator of ecological risk.  相似文献   

19.
The growth rates of 13 species of abundant red tide algae in media with different iron species complexed with microbial siderophores (Ferrichrome and Ferrioxamine) and Fe‐Catechol were investigated. Our study demonstrated that the Fe‐chelates (at molar ratios = 1:1) were bioavailable to some red tide species. In Fe‐Catechol medium, growth was observed for the raphidophyte Heterosigma akashiwo, the dinoflagellates Heterocapsa circularisquama and Heterocapsa triquetra, the diatom Ditylum brightwellii, the cryptophyte Rhodomonas ovalis, the chlorophyte Oltmannsiellopsis viridis, and the haptophyte Cricosphaera roscoffensis. In Ferrioxamine medium, we found the growth of the dinoflagellate Karenia mikimotoi, the diatom Ditylum brightwellii, and the cryptophyte Rhodomonas ovalis. But, the existence of higher ligand concentrations (molar ratios ≥ 1:10) decreased the growth rates of most red tide species that were examined. Furthermore, all red tide species examined were not able to grow in Ferrichrome medium. In particular, the Chattonella species examined did not grow in the presence of Fe‐chelates. These results suggest that bioavailability of iron depends not only on ligand species, but also on the concentration of the ligands; moreover, microbial siderophores may play an important role in controlling the uptake of iron complexed with organic materials that exist in coastal water and the formation of red tides in coastal areas.  相似文献   

20.
有机改性粘土去除有害赤潮藻的研究   总被引:25,自引:0,他引:25  
本研究以阳离子表面活性剂十六烷基三甲基溴化铵为改性材料,通过粘土颗粒的表面吸附及离子交换作用对粘土进行了表面改性,并以常见于我国沿海的有害赤潮生物种-东海原甲藻(Prorocentrum donghaiense)为目标生物,研究了有机粘土对该藻的去除效果.结果表明,改性后的粘土具有极强的去除赤潮生物能力,当有机粘土的用量为0.01g·L-1时,在24h内东海原甲藻的去除率大于95%。而未经改性处理的原土在相同用量下没有表现出对东海原甲藻的有效去除作用,这表明通过有机改性能显著增强粘土的除藻能力.对有机粘土高效去除机理分析表明。有机粘土表面静电作用、季铵盐离子亲脂性长脂肪链的“网捕”作用及粘土颗粒表面局部高浓度季铵盐离子的灭杀作用是有机粘土具有强去除藻细胞能力的主要原因.  相似文献   

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